As I mentioned above, learning a language is a self-teaching process. You might need a teacher to help you, to give you an idea or direction, a little bit of explanation or correction.
You don’t need to have a native speaker as a teacher. It is not always good. Some non-native speakers are even better because they are trained teachers; they went through the language training, so they know how to explain and what to explain. Some native Russian speakers are not so educated, and you might not find what you are looking for. If your native-speaker teacher is not educated, it means her or his speech is not correct, and you will speak like a low-class person; if that doesn’t bother you, it’s OK.